Addressing the Mutual Interference in Uplink ISAC Receivers: A Projection Method

TL;DR

This paper introduces a projection-based method for uplink ISAC receivers that effectively mitigates mutual interference, enhancing signal detection and target estimation performance compared to traditional SIC approaches.

Contribution

A novel projection scheme transforms joint detection and estimation into a multi-snapshot detection problem, improving SNR and ergodic rate in ISAC systems.

Findings

Higher SNR and ergodic rate than SIC methods

Effective mitigation of mutual interference in uplink ISAC

Joint snapshot processing enhances sensing and communication performance

Abstract

Dual function radar and communication (DFRC) is a promising research direction within integrated sensing and communication (ISAC), improving hardware and spectrum efficiency by merging sensing and communication (S&C) functionalities into a shared platform. However, the DFRC receiver (DFRC-R) is tasked with both uplink communication signal detection and simultaneously target-related parameter estimation from the echoes, leading to issues with mutual interference. In this paper, a projection-based scheme is proposed to equivalently transform the joint signal detection and target estimation problem into a joint signal detection process across multiple snapshots. Compared with conventional successive interference cancellation (SIC) schemes, our proposed approach achieves a higher signal-to-noise ratio (SNR), and a higher ergodic rate when the radar signal is non-negligible. Nonetheless, it introduces an ill-conditioned signal detection problem, which is addressed using a non-linear detector. By jointly processing an increased number of snapshots, the proposed scheme can achieve high S&C performance simultaneously.